Dose and cost considerations for relocation after nuclear accidents

The results of a comprehensive study of the dose and cost considerations for relocation after nuclear accidents are presented in this paper. These results include the quantification of the dependence of area affected by relocation on dose intervention level and source term, the countermeasures implementation cost-benefit estimate, as well as the application of cost-benefit analysis to optimize the dose intervention level for relocation. In order to explicitly consider the distribution of individual dose among the exposed population to determine the optimal dose intervention level for relocation, the concept of individual dose evaluation function has been introduced in the present work.

[The effects of phorbol 12-myristate 13-acetate and microcystine-LR on calcium channel in resistance vascular smooth muscle cells in SHRsp]

OBJECTIVE

To investigate the effects of phorbol 12-myristate 13-acetate (PMA) and microcystine-LR (MCYST-LR) on the whole-cell barium currenta of voltage-dependent calcium channels (VDCs) of the resistance vascular smooth muscle cells (VSMC) from the A4-A5 branches of mesenteric artery in stroke-prone spontaneously hypertensive rats (SHRsp) and its normotensive control Wistar rats.

METHODS

Using the whole-cell Ba2+ current recording of the patch clamp technique.

RESULTS

It was found that PMA, a protein kinase C (PKC) agonist or MCYST-LR, a protein phosphatase IA and IIA inhibitor by which the enhancement of phosphorylation induced could apparently activate the VDCs of the visceral resistance VSMC.

CONCLUSIONS

This activation would be significantly potentiated during hypertension, in which the increase of L-type calcium channel openings induced by PMA was obviously manifest, as the T-type calcium channel activity weakly potentiated. In normotensive Wistar rats, the increase of T-type calcium channel openings was greater than that of SHRsp. However, the effect of MCYST-LR appeared that only the increase of L-type calcium channel current in SHRsp was significant. It is suggested that the action of PKC and/or phosphorylation on the different components of calcium currents should be emphasized in the investigation of the mechanism in the increase in peripheral resistance during hypertension.

[Sequence analysis of Ad7 vaccine strain 87 mu-97.4 mu fragment]

Adenovirus 7 vaccine strain(Ad7v) possesses potentiality to be used as a vector for producing recombinant vaccine. In order to construct Ad7 vector, the nucleotide sequence of a 3698 bp fragment(87 to 97.4 mu) of the virus DNA was analysed. The fragment encodes three ORFs namely, one ORF of early region 4(E4), one ORF of early region 3 and one ORF of fiber protein. The predicted amino acids of three ORFs(ORF 8.1 kD, 42.8 kD and 10.3 kD) share 33%, 43% and 44% homology with Ad2 E4 corresponding regions (ORF 3, ORF 4 and ORF 6/7) respectively. A comparison of the nucleotide and amino acid sequences of those fiber ORF demonstrated a higher homology between Ad7v and prototype strains of Ad7v than those between Ad7v and Ad7h. The Ad7v E3 15.4 kD protein shares 86%, 88%, 90% and 98.5% amino acid homology with the equivalent region of ad7h E3 15.3 kD protein, Ad4 E3 region 15 kD protein, Ad3 E3 15.3 kD and Ad7p E3 15.3 kD protein protein respectively, but only 68% with Ad2 E3 14.7 kD protein.

Effects of carbon source on expression of F0 genes and on the stoichiometry of the c subunit in the F1F0 ATPase of Escherichia coli

Expression of the genes for the membrane-bound F0 sector of the Escherichia coli F1F0 proton-translocating ATPase can respond to changes in metabolic conditions, and these changes are reflected in alterations in the subunit stoichiometry of the oligomeric F0 proton channel. Transcriptional and translational lacZ fusions to the promoter and to two F0 genes show that, during growth on the nonfermentable carbon source succinate, transcription of the operon and translation of uncB, encoding the a subunit of F0, are higher than during growth on glucose. In contrast, translation of the uncE gene, encoding the c subunit of F0, is higher during growth on glucose than during growth on succinate. Translation rates of both uncB and uncE change as culture density increases, but transcription rates do not. Quantitation of the c stoichiometry shows that more c subunits are assembled into the F1F0 ATPase in cells grown on glucose than in cells grown on succinate. E. coli therefore appears to have a mechanism for regulating the composition and, presumably, the function of the ATPase in response to metabolic circumstances.

[Effects of GTP gamma S and GDP beta S on calcium channels of resistance vascular smooth muscle cells in SHRsp]

OBJECTIVE

To investigate the effects of GTP gamma S and GDP beta S on the whole-cell barium currents of voltage-dependent calcium channels (VDC) of the vascular smooth muscle cells (VSMC) from the A4-A5 branches in SHRSP mesenteric artery.

METHODS

Using the whole-cell Ba2+ current recording of the patch clamp technique.

RESULTS

(1) GTP gamma S, a G-protein agonist, increased whole-cell Ba2+ currents both of SHRSP and Wistar, but SHRSP with a higher ratio of amplitude change than Wistar. In addition, GTP gamma S shifted D infinity to right both in SHRSP and Wistar, but D infinity shifted more in SHRSP than that in Wistar. (2) GDP beta S, a G-protein antagonist, decreased whole-cell Ba2+ currents both of SHRSP and Wistar, but SHRSP with a higher inhibition ratio of amplitude change than Wistar. In addition, GDP beta S shifted F infinity to right and in SHRSP shifted more than control under HP = -80 mV.

CONCLUSIONS

The G-protein mechanism may promote Ca2+ influx and contribute to the increase of peripheral resistance during hypertension.

[The parapharyngeal space tumour of children: reports of 4 cases]

In 1986-1996, four childish patients with parapharyngeal space tumour were treated in our hospital. In the beginning, we ought to define the size and range by CT scanning. The second, we excized it from neck-flank. The patients had a satisfying effect after surgical operation. Meantimes, it's necessary to protect the important vessel and nerve in surgical operation.

[DNA cloning of Ad7 vaccine strain and sequence analysis of its Sma I H fragment]

Human adenoviruses have been a hot topic of study because of their potential utility for gene therapy and development of live viral vectored vaccines. Adenovirus types 4 and 7 have been given orally as vaccines for prevention of acute respiratory infections caused by these serotypes of adenovirus in U.S. army recruits for more than 30 years. Therefore, the advantage of using Ad4 and Ad7 as vectors in the development of oral live recombinant vaccine is obvious. For constructing Ad7 vector, 10.8-100 mu DNA of Ad7 vaccine strain has been cloned. The Sma I H fragment was sequenced using Ad7 DNA as a template and then the fragment was cloned by PCR. For verifying the sequence the fragment was sequenced again. The strategy we used to clone terminal end of adenovirus is reliable and practicable.

[Effect of SNP on KCa of resistance vascular smooth muscle cell membrane in SHRsp]

OBJECTIVE

To investigate the effect of sodium nitroprusside (SNP) on calcium activated potassium channels (KCa) of mesenteric arterial A4-A5 branches resistence vascular smooth muscle cell membrane in Stroke-prone Spontaneously Hypertensive Rats (SHRsp) and its normotensive control WKY rats.

METHODS

Cell-attached patch clamp technique was used.

RESULTS

It was found that SNP could activate the KCa of the resistance vascular smooth muscle in both SHRsp and WKY. Under the same dose of SNP (1 nmol/L), the conductance and channel current amplitude etc. of the activated KCa in SHRsp were smaller than that in WKY rats. Given the same dose of 8-Br-cGMP (10 mumol/L), the cGMP activation of SHRsp KCa was less potentiated than that of WKY, appeared very similar to SNP/NO activation.

CONCLUSIONS

The results suggested the KCa of hypertensive resistance vascular smooth muscle membrane appearing weaker response to relaxing factor EDRF/NO.

Ionic basis of ryanodine's negative chronotropic effect on pacemaker cells isolated from the sinoatrial node

Spontaneous electrical activity and indo 1 fluorescence ratios were recorded simultaneously in cultured pacemaker cells isolated from the rabbit sinoatrial node. Ryanodine (10 microM) reduced the amplitude of action potential-induced intracellular Ca2+ (Ca2+i) transients by 19 +/- 3%, increased the time constant for their decay by 51 +/- 5%, and slowed spontaneous firing by 32 +/- 3%. 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA)-acetoxymethyl ester (AM; 25 microM) inhibited the Ca2+i transients and slowed spontaneous firing by 28 +/- 4%. Ryanodine did not alter hyperpolarization-activated or time-independent inward current, but it reduced the sum of L- and T-type Ca2+ currents (ICa,L and ICa,T) in both the presence and absence of BAPTA-AM. In contrast, ICa,L was unchanged by ryanodine. Slow inward current tails, presumed to be Na/Ca exchange current (INa/Ca), were abolished by BAPTA or ryanodine. The results suggest that a decrement of ICa,T, due to reduction of the intracellular Ca2+ concentration or a direct effect of ryanodine on T-type Ca2+ channels, contributes to the negative chronotropic effect. Another possibility, based primarily on theory and results in other preparations, is that a reduction of INa/Ca, as a consequence of the smaller action potential-induced Ca2+i transients, contributes to the effect of ryanodine.

[Diagnosis and treatment of mediastinal tumor by VATS]

Twenty-eight patients with mediastinal tumors underwent thoracoscopic operation, among which 22 received the resection of mediastinal tumor including mediastinal cyst (9), teratoma (5), neurogenic tumor (5), thymoma (1), vagothyrophyma (1), and lipoma (1), and 6 patients received diagnostic biopsy of mediastinal tumor. The preliminary results were promising. The experience of thoracoscopic operation on mediastinal tumor are discussed in this article and VATS is regarded as a new diagnostic and treating method which is superior to conventional thoractomy on some kinds of mediastinal diseases.

[The mutiplication of Sindbis virus and host BHK-21 cell apoptosis]

The process of apoptosis of BHK-21 cells induced by Sindbis virus (SbV) infection is reported here in details. The nuclear DNA cleavage can be first detected at 6 h after SbV infection, followed by the chromatin margination and condensation at 12 h and the DNA ladder can be detected at 24 h after infection. The details of apoptosis body's formation can be revealed by electron microscopy: First, the outer nuclear membrane protrudes where the condensed chromatin accumulates, then the chromatin get into the budding area with the inner nuclear membrane and separate from the nuclear. Progressively, we cloned the gene of SbV nonstructure protein 2 (nsP2) into the eukaryotic expression vector pMAMneo, and it can be expressed transiently. The DNA cleavages, the basic characteristics of apoptosis also can be detected in some cells. Together with the sequence analysis of nsP2 and the other former results, we conclude that the nsP2 may have direct relation with the SbV-induced apoptosis.

[Nuclear reconstitution around purified E. coli DNA in cell-free extracts of Xenopus laevis eggs]

In recent years we have succeeded in inducing various exogenous DNA to assembly typical nuclei in cell-free Xenopus egg extracts. However, it is not clear if prokaryotic chromosomal DNA can also form the nucleus in this eukaryotic system. In our experiment, we used the purified E. coli. chromosomal DNA to reconstitute the nucleus in the nuclear reconstitution extracts and found that typical nuclei can also be assembled around added DNA. We observed the process of nuclear reconstitution by using light microscopy and electronic microscopy. The scanning results of chromatin-like materials and assembled nuclei by microspectrophotometer showed that E. coli, chromosal DNA underwent obvious change from condensation to decondensation during nuclear reconstitution. Incorporation of alpha-32P-dCTP into DNA suggested that the reconstituted nuclei were capable of DNA replication.

[Determination of chlorosilanes by gas chromatography]

Chlorosilanes are the essential raw material of SiC fibre made by "CVD (chemical vapour deposition)" method. The purity of chlorosilane affects the quality of SiC fibre obtained. Therefore, a simple and reliable method for the determination of the constituent of chlorosilane is needed. A gas chromatographic method for quantitative analysis of chlorosilane is described in this paper. The gas chromatographic conditions were as follows: column, 10% diethyl phthalate on 6201 support (60-80 mesh), 3m x 5mm i.d. stainless-steel column; column temp., 60 degrees C; injection temp., 110 degrees C; thermal conductivity detector temp., 140 degrees C carrier gas H2 with flow rate of 60 mL/min. The results show that the method is simple and rapid, and has good precision and reproducibility. The coefficient of variation of the method was less than 1% (n = 6).

Cloning, expression and chromosomal mapping of human lysosomal sialidase and characterization of mutations in sialidosis

Sialidase (neuraminidase, EC 3.2.1.18) catalyses the hydrolysis of terminal sialic acid residues of glyconjugates. Sialidase has been well studied in viruses and bacteria where it destroys the sialic acid-containing receptors at the surface of host cells, and mobilizes bacterial nutrients. In mammals, three types of sialidases, lysosomal, plasma membrane and cytosolic, have been described. For lysosomal sialidase in humans, the primary genetic deficiency results in an autosomal recessive disease, sialidosis, associated with tissue accumulation and urinary excretion of sialylated oligosaccharides and glycolipids. Sialidosis includes two main clinical variants: late-onset, sialidosis type I, characterized by bilateral macular cherry-red spots and myoclonus, and infantile-onset, sialidosis type II, characterized by skeletal dysplasia, mental retardation and hepatosplenomegaly. We report the identification of human lysosomal sialidase cDNA, its cloning, sequencing and expression. Examination of six sialidosis patients revealed three mutations, one frameshift insertion and two missense. We mapped the lysosomal sialidase gene to human chromosome 6 (6p21.3), which is consistent with the previous chromosomal assignment of this gene in proximity to the HLA locus.

[Experience of surgical treatment of patients with N2 lung cancer]

From January 1987 to December 1993, 426 patients with lung cancer were operated in our hospital, among which 159 patients were diagnosed postoperatively to be N2 disease by pathology including 81 central type and 78 peripheral type lung cancer. Radical operations were performed on 135 cases, palliative operations on 24 cases. Follow up study: one-year survival rate was 71.7%, three-year survival rate 29.0% and five-year survival rate 21.7%. The main factors affecting operative results are tumor cell type, the number and location of metastatic lymph nodes and the thoroughness of dissection. Tumor staging, except T4 tumor is not a main factor influencing prognosis. The indications of operation performed on N2 lung cancer and the necessity of extensive nodal exenteration are also discussed in this article. We consider extensive hilar and mediastinal nodal exenteration necessary in order to achieve radical resection and good prognosis.

Fragile site and interstitial telomere repeat sequences at the fusion point of a de novo (Y;13) translocation

We describe a novel fragile site in a rearranged chromosome, associated with the presence of telomeric repeat sequences at the fusion point of a translocation between chromosomes 13 and Y. The case reported in this study shows a de novo (Y;13) translocation, which appears to represent fusion of an apparently intact chromosome Y with a chromosome 13 that has lost only part of its short arm. Ten percent of the cells show a normal karyotype without the (Y;13) translocation. Molecular cytogenetic studies of the derived Y;13 chromosome revealed three hybridization sites of the telomeric probes-one at each end and one at the breakpoint junction. A fragile site is also observed in the intrachromosomic telomeric region. This coincidence suggests that the telomere repeat sequences (TTAGGG)n, when present at an interstitial chromosomal location, can promote the formation of a novel fragile site.

Phosphatidylserine-mediated adhesion of T-cells to endothelial cells

Phosphatidylserine was exposed on the surface of human umbilical endothelial cells (ECV304) a few minutes after adding thrombin in vitro, as monitored by prothrombinase assays with and without annexin V. Jurkat T cells adhered to the thrombin-treated cells. The adhesion was inhibited by annexin V, indicating that it was mediated by exposed phosphatidylserine on the endothelial cells.

[The relationship between prognosis of esophageal squamous carcinoma and Langerhans cell]

The operative tumor specimen of esophageal squamous carcinoma were studied with immunohistochemical (ABC) method S-100 protein staining. Under the light microscopy, we observed the morphology, number and distribution of Langerhan's cells (LC) in different portion of the tumor mass and its relationship with the pathological staging in 167 cases. We observed also the relationship between LC and the postoperative survival period in 127 cases followed for more than 3 years. These results suggested found that positive relation between the number of LC in the cancer nest and in the lymphfollicle with the increasing of TNM classification. The number of LC in the cancer nest significantly increased in state III and IV cases than II cases. On the contrary, the number of LC in the peritumor and interstitial tissue decreased while the TNM classification was increasing. These findings suggested that the survival period was shorter in patients whose LC had increased in the cancer nest, whereas the survival period would be longer in those patients whose LC had increased in the tissue around the tumor mass, in the mucosa near the tumor as well as in the interstitial tissue. These two points might be used as an immunological para-meter for the assessment of the prognosis.

[Lipopolysaccharide (LPS) induced pulmonary inflammatory response and effects of TNF in immunocompromised host (ICH)]

OBJECTIVE

To investigate the pulmonary inflammatory response and TNF-mediated effects in ICH.

METHODS

ICH models of guinea pigs were induced successfully by receiving daily intraperitoneal injections of cyclophosphamide (15mg.kg-1.d-1) plus daily subcutaneous injection of cortisone acetate (100mg.kg-1.d-1) for a total of 7 consecutive days. On the day after the final dose of drugs, guinea pigs were challenged intratracheally with LPS (200 micrograms/animal) and were lavaged before and 1, 3, 5, 8, 24 hours after challenged, respectively.

RESULTS

Five hours after LPS challenged, total counts of bronchoalveolar fluid (BALF) cells and the proportion of PMN increased significantly. Although the counts of both PAM and PMN increased, the proportion of PAM decreased gradually accompanied by increase of the proportion of PMNs. Hematoxylin eosin stained lung sections after challenged with LPS showed an acute intraalveolar inflammatory response. After intra-tracheal injection of LPS, the TNF level in BALF progressively increased. Both the TNF level and PMN count started to increase at 1 hour after LPS challenge, peaked at 5 hours. The TNF level in serum did not increase markedly after intratracheal injection of LPS. In the development of an inflammatory response, a large amount of TNF were released in BALF, the level of TNF in BALF was closely matched the influx of PMN.

CONCLUSIONS

The data suggested that TNF was one of the cytokines which mediated influx of PMNs and inflammation. High level of TNF released in BALF of ICH could induce the lung injury. The systemic inflammatory response of ICH was involving immunosuppressed state after intratracheal injection of LPS, however, strong intraalveolar inflammatory response still occurred, which reflected the phenomenon of "compartmentalization" in inflammatory response.

The use of micromachined surfaces to investigate the cell behavioural factors essential to osseointegration

OBJECTIVE

Although currently available implants can be used to achieve osseointegration under well-defined conditions, a greater understanding of cell behaviour is required to improve the designs and embark on actual tissue engineering.

MATERIALS AND METHODS

We employed micromachined substrata to investigate some of the main behavioural responses of osteoblasts from rat fetal calvaria to surface topography. In particular, confocal laser scanning microscopy (CLSM), differential interference contrast microscopy, time-lapse cinemicrography, immunofluorescence, digital radiography and image analysis were used to investigate cell adhesion, cell shape and cytoskeleton distribution, tissue organization, cell differentiation, and microenvironment.

RESULTS AND CONCLUSIONS

A grooved surface permitted the attachment of more cells than a smooth one. Cell shape and cytoskeleton were strikingly influenced as early as 20 min after cell attachment, when the cytoskeleton begins to align with the topography. Some grooved surfaces appeared to promote osteogenesis in vitro as assessed by the production of bone-like nodules. Moreover, these nodules align with the topography in vitro, and preliminary results indicate that bone-like tissue also aligns with grooves when such surfaces are implanted in vivo.

[Thoracoscopic esophagectomy for esophageal carcinoma: report of 8 patients]

Eight patients with esophageal carcinoma were treated by VATS in our hospital since March 1995. Of the 8 patients, 2 had lower-middle segment esophageal carcinoma and 6 middle segment. The operations performed on seven patients were successful except one that had to be changed to thoractomy as a result of invasion of tumor. Techniques of VATS in treating esophageal carcinoma and indication were discussed.

[Basic study on evaluation of the fundus with monochromatic photography]

By using the monochromatic fundus photographic system we developed, fundus pictures of 93 normal subjects were taken under the illumination of 10 lights with varying wavelengths. A densitometer was used for evaluating these photographic results. Optimal illumination lights were selected respectively for photography of different layers of fundus details. The results showed that the degrees of contrast at the macula, optic nerve fiber layer, physiological cup of papilla, retinal artery and vein, optic nerve head, choroid striae are the highest under the illumination of light with wavelength 478nm, 478nm, 530nm, 570nm, 628nm and 628nm respectively. The visibility of nerve fiber layer in the subjects over 50 years old is the highest under the illumination of light with a wavelength of 530nm. However, the degrees of contrast of all their fundus structural details, especially the macula and nerve fiber layer, are lower than those of subjects under 50 years old photographed with the corresponding lights with optimal wavelengths (P < 0.01).

Biological activity assays of cell-free reassembled nuclei--injecting cell-free reassembled nuclei into unfertilized eggs can induce the eggs to cleave and reconstitute asters, and the injected nuclei undergo cell cycle changes

Nucleus may reassemble spontaneously in cell-free mixture of HeLa metaphase chromosomes, Xenopus egg extracts and ATP-regenerating system, and the nucleus shows some biological activities. It is found that, after being injected into unfertilized mature eggs, the cell-free reassembled nuclei can cause the eggs to cleave and reconstitute asters in their cytoplasm, and the injected nuclei undergo changes in response to cell cycle regulators stored in the eggs, and that reinjecting cytostatic factors (CSF) into the eggs can stabilize the eggs in mitotic phase, cause the nuclei disassembly and chromatin condensation to chromosomes.

[The distribution of SbV nonstructural protein 2 (nsP2) in host cell]

The distribution of SbV nsP2 has been observed by means of immunolabelling electron microscopy. The results showed that SbV nsP2 existed both in the cytoplasm and in the nucleus of host cell. When the cDNA of SbV nsP2 was transfected in host cell, the nsP2 also accumulates in the nucleus.

Effects of FMLP and LPS on [Ca2+]i of peritoneal exudate polymorphonuclear leukocytes following onset of inflammation

Because a general study of activated neutrophils may have relevance to periodontal diseases and accompanying inflammation, we studied a function of mouse polymorphonuclear leukocytes (PMNs) that exude into the peritoneal cavity in response to inflammation caused by i.p. injection of 2% casein. The effects of E. coli-lipopolysaccharide (E-LPS) and a chemotactic factor, N-formyl-N-methionyl-N-leucyl-L-phenylalanine (FMLP), on the level of intracellular calcium ([Ca2+]i) in these PMNs were examined. From analysis made with a laser cytometer (ACAS 570), the PMNs in exudates harvested 3-9 h after the onset of inflammation were shown to undergo [Ca2+]i elevation in response to 10(-6) M FMLP. The peak concentration of [Ca2+]i elicited by FMLP was highest in exudate cells 6 h after casein injection. In addition, about 65% of the PMNs in the 3-h exudate were FMLP sensitive displaying an elevated [Ca2+]i, whereas more than 85% of them in 6- and 9-h exudates became FMLP sensitive. Also, the maximum level of [Ca2+]i after FMLP stimulation was potentiated by pretreatment of the cells with E-LPS (0.2 microgram/ml). The present study suggests that PMNs induced by casein injection and appearing in mouse peritoneal exudate at different times possess significantly different ability to undergo [Ca2+]i elevation, and different susceptibility toward a chemotactic factor, FMLP.

Lack of effect of recombinant platelet-derived growth factor on human neutrophil function

Platelet-derived growth factor (PDGF) has been reported to induce chemotaxis, degranulation, and superoxide anion generation, and to increase the expression of CD11b/CD18 in human neutrophils; hence, it has been proposed as an important regulator of neutrophil function. Most of the studies on PDGF, however, have been complicated by the use of nonrecombinant PDGF or the use of mixed leukocyte cell preparations. Assessment of the effects of recombinant human PDGF-AB or -BB which display agonist activity against both PDGF receptor subtypes failed to demonstrate any effect of this peptide on neutrophil shape change, respiratory burst activity, CD11/CD18, or CD62-L expression, inositol 1,4,5-trisphosphate accumulation, or phosphorylation of mitogen-activated protein kinase. This apparent lack of effect of PDGF was consistent with our findings that neutrophils display no specific 125I-PDGF-AB or -BB binding and lack detectable mRNA for PDGF alpha-receptor and beta-receptors. These data indicate that human neutrophils do not possess functional PDGF receptors and question previous reports of a functional effect of this peptide in these cells.

Lack of effect of recombinant platelet-derived growth factor on human neutrophil function

Platelet-derived growth factor (PDGF) has been reported to induce chemotaxis, degranulation, and superoxide anion generation, and to increase the expression of CD11b/CD18 in human neutrophils; hence, it has been proposed as an important regulator of neutrophil function. Most of the studies on PDGF, however, have been complicated by the use of nonrecombinant PDGF or the use of mixed leukocyte cell preparations. Assessment of the effects of recombinant human PDGF-AB or -BB which display agonist activity against both PDGF receptor subtypes failed to demonstrate any effect of this peptide on neutrophil shape change, respiratory burst activity, CD11/CD18, or CD62-L expression, inositol 1,4,5-trisphosphate accumulation, or phosphorylation of mitogen-activated protein kinase. This apparent lack of effect of PDGF was consistent with our findings that neutrophils display no specific 125I-PDGF-AB or -BB binding and lack detectable mRNA for PDGF alpha-receptor and beta-receptors. These data indicate that human neutrophils do not possess functional PDGF receptors and question previous reports of a functional effect of this peptide in these cells.

Diagnostic imaging of the larynx: autofluorescence of laryngeal tumours using the helium-cadmium laser

The use of tissue autofluorescence for the detection and localization of cancer of the larynx is described. In this pilot study, eight patients with probable carcinoma of the vocal folds underwent laryngoscopy in which the tissue autofluorescence spectra of normal and pathologically confirmed tumour tissue were acquired in vivo. Fluorescence images of the suspect areas were also acquired using the LIFE system (Xillix Technologies Corp.). The results suggest that the autofluorescence properties of laryngeal tissue, under 442 nm illumination, are similar to those of bronchial tissue and that the LIFE system has the potential to increase the accuracy of staging of cancer of the larynx and also to allow earlier diagnosis of tumours and their recurrence.

Optical properties of normal and carcinomatous bronchial tissue

To understand better the optical characteristics and autofluorescence properties of normal and carcinomatous bronchial tissue, we measured the absorption coefficient, scattering coefficient, and anisotropy factor from 400 to 700 nm. We made the measurements by using an integrating sphere with a collimated white-light beam to measure total reflectance and transmittance of samples. The unscattered transmittance of the samples was measured through polarized on-axis light detection. The inverse adding-doubling solution was utilized to solve the equation of radiative transfer and to determine the absorption coefficient and reduced scattering coefficient. The scattering coefficient and anisotropy factor were derived from the unscattered transmittance of the sample and the reduced scattering coefficient. The measured parameters allow us to simulate photon propagation in normal bronchial and tumoral tissue by using Monte Carlo modeling.

[Nuclear reconstitution around purified HeLa chromosomes in a cell-free system from Xenopus eggs]

Activated Xenopus egg extracts are capable of reconstituting nucleus around the added DNA or chromatin. To understand better the nuclear reconstitution process and the structure of the assembled nucleus, we have developed a cell-free system using activated Xenopus egg extracts and metaphase chromosomes of HeLa cells. We demonstrate that the extracts are efficient promoting the decondensation of the metaphase chromosomes and the nuclear reconstitution around the chromosomes, and that the nuclear reconstitution is a precise process. The reassembled nucleus possesses a typical nuclear envelope, pore complexes, nuclear lamina, nuclear matrix, chromatin, etc., as shown by electron microscopy, embedment and embedment-free electron microscopy, and immunofluorescence method. We also found that the annulate lamellae directly take part in nuclear envelope and pore complex reconstitution by fusing with the double membrane, having reassembled on the surface of chromatin/chromosomes.

Regulation of inhibin secretion in human placental cell culture by epidermal growth factor, transforming growth factors, and activin

In this study, the effects of epidermal growth factor (EGF), transforming growth factor-alpha (TGF alpha), TGF beta 1, and activin-A on inhibin secretion were investigated in primary culture of human placental cells. Immunoreactive inhibin in the culture medium was measured by immunoenzymatic assay. EGF stimulated testosterone-induced inhibin secretion in placental cells. Although testosterone alone induced only a slight enhancement of inhibin release in the culture, treatment of trophoblast cells with EGF and testosterone caused a significant increase in inhibin secretion, with immunoreactive inhibin levels much higher than those of testosterone or EGF alone. TGF alpha combined with human placental lactogen (hPL) had a stimulatory effect on inhibin secretion in placental cell culture. Simple addition of either TGF alpha or hPL to the culture did not show any effect on inhibin secretion in placental cells. A remarkable augmentation of inhibin secretion was obtained after the trophoblasts were exposed to both TGF alpha and hPL simultaneously. TGF beta 1 and activin-A showed synergistic effects to suppress inhibin secretion in placental cells. TGF beta 1 alone did not show any action on inhibin secretion, and activin-A alone induced a small decrease in inhibin release in the culture. In the presence of activin-A, addition of TGF beta 1 to the culture induced a profound decrease in immunoreactive inhibin levels in the medium. Activin-A could also suppress hCG-induced inhibin secretion in placental cells. Addition of hCG alone resulted in a small, but not significant, increase in inhibin release in the cultured cells, whereas the presence of activin-A combined with hCG in the culture conversely decreased inhibin secretion in the culture, with immunoreactive inhibin levels significantly lower than those in the presence of hCG or activin-A alone. These findings suggest that EGF and TGF alpha, alone or in combination with other hormones, may be stimulators, and TGF beta and activin may act as suppressors of inhibin secretion in human placental cells.

Prostaglandins stimulate the secretion of inhibin from human placental cells

In this study, the effects of prostaglandins (PGs) on inhibin secretion were investigated in primary culture of human placental cells. Isolated trophoblast cells were cultured for 2-5 days with PGE1, PGE2, 6-keto-PGF1 alpha, PGF2 alpha, and thromboxane B2. Inhibin levels in the culture medium were measured by immunoenzymatic assay. PGs significantly stimulated inhibin secretion in the cell culture. The addition of PGs (1 nM to 10 microM) to the culture resulted in dose-dependent increases in inhibin levels in the medium. At a dose of 10 microM, inhibin levels in the medium were increased by 35.2-172.5% compared to the control value. Compared with the efficacies of these PGs, PGE2 and PGF2 alpha enhanced inhibin secretion more potently than other tested PGs. A close correlation between the effects of PGs and the number of trophoblasts seeded in the culture was observed, with an optimal response of the cells to PGs at 1.0-2.0 x 10(6) cells/well. Time-course studies showed that a significant increment in inhibin levels in the PG-treated culture occurred after 48-120 h, but not during the first 24 h, of the culture, indicating a possible involvement of PGs in inhibin biosynthesis in the cells. Epidermal growth factor (EGF) could enhance PG-stimulated inhibin releases in the cell culture. Treatment with EGF (100 ng/mL) increased inhibin in the medium by 83.3% (ED50) in the presence of PGE2 or by 70.3% (ED50) in the presence of PGF2 alpha compared to the control values. The addition of 8-bromo-cAMP (100 microM) and cholera toxin (1000 ng/mL) to the culture also enhanced basal and PG-induced inhibin secretion, but the addition of the 4-bromo-calcium ionophore A23187 (1 microM) did not alter inhibin releases, suggesting that the stimulatory effects of PGs on inhibin secretion in placental cells may be mediated through the cAMP pathway. In the cell cultures treated with PGE and PGF2 alpha, there was no change in cell growth or intracellular DNA content, as measured by 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide assay and DNA determination with fluorescence spectrophotometry. Morphological studies showed that PGE2 alpha (1 microM), alone or combined with EGF (100 ng/mL), significantly accelerated the process of differentiation from cytotrophoblasts to syncytiotrophoblasts, indicating that the actions of PGs may be related to their effects on syncytial transformation, rather than cellular proliferation.(ABSTRACT TRUNCATED AT 400 WORDS)

A fundus photographic method with narrow spectral band luminance

We perfected the narrow spectral band fundus photographic system using interference filters at the wavelengths of 417, 478, 500, 530, 547, 570, 589, 607, 628 and 648 nm. Tests about the light penetration of filters and exposure of various brand films were made on this system. Studies of the contrast of fundal tissues and structures under the different narrow spectral band light were made on 43 Chinese fellow eyes. The results indicates that the interference filters of 570 nm have the highest light penetration. Kodak and Gongyuan films (make in China) are the optimal ones. Narrow spectral band fundus photography can eliminate the chromatic aberration and therefore improve the documentation of fundal details, enhance the contrast of pictures as compared with routine white light fundus photography.

Effect of epidermal growth factor on inhibin secretion in human placental cell culture

The effect of epidermal growth factor (EGF) on inhibin secretion was investigated in a primary culture of human placental cells. Dissociated cells were cultured with EGF, FSH, 8-Br-cAMP, and two agents known to increase intracellular cAMP. Inhibin level in the culture medium was measured by immunoenzymatic assay. Addition of EGF (0.1-1000 ng/ml) in the cell culture induced a dose-dependent increase of inhibin levels in the medium after 2 days of culture. Greater response of placental cells to EGF in the inhibin secretion occurred at the doses of 10-1000 ng/ml, where inhibin levels in the medium increased by 84.9-111.5% compared to the control (P < 0.01). FSH stimulated the inhibin secretion in the placental cells. EGF combined with FSH resulted in a greater response of placental cells in inhibin secretion. Addition of FSH (30 ng/ml) and EGF (0.1-1000 ng/ml) in the culture induced inhibin levels significantly higher than that of either FSH alone or EGF alone (P < 0.01). The effect of EGF on inhibin secretion was closely correlated with the seeding density of trophoblasts and the time course of culture. Obvious effect of EGF was found at the number of 1-2 x 10(6) cells per well and after 36-48 h of culture. Addition of 8-Br-cAMP, cholera toxin, or forskolin in the culture increased the inhibin levels more than 6-fold, 5-fold, and 2-fold, compared to the controls, respectively. When EGF combined with one of these agents was added in the culture, the inhibin in the medium increased to a level higher than those with the individual agents alone. EGF resulted in an increase in basal and cAMP induced human CG secretions in the trophoblasts in a similar manner as in the inhibin secretion. However, the effect of EGF on the proliferation of trophoblasts was not observed by measurements of the cell growth with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and DNA content in the cells with fluorescence spectrophotometry. Morphological study showed that EGF induced trophoblasts to differentiate and form syncytium. These data suggest that EGF stimulates inhibin secretion in human placental cells in vitro. EGF and its interaction with other hormones or growth factors may play an important role in the complicated hormonal regulation during human pregnancy.

Prenatal identification of a 45,X/46,Xder(Y) mosaicism and confirmation by high resolution cytogenetics and fluorescence in situ hybridization

A 45,X/46,Xder(Y) mosaicism detected prenatally was shown to have a rare Y inversion-duplication or Y/Y translocation which can only be identified by a combination of high resolution cytogenetics and fluorescence in situ hybridization. The present data indicate the usefulness and importance of chromosome-specific probes in the identification and characterization of chromosome rearrangements.

[Protective effects of Panax quinquefolium saponin on oxidative damage of cultured rat cardiac cells]

When cultured cardiac cells of rats were exposed to X-XOD containing medium, the absolute values of electronic parameters were decreased the percentage of beating clusters reduced and the microscopic structure destroyed. PQS significantly converted all the indices, which shows that PQS can protect the cells from oxidative damage.

Changes in bioactive and immunoactive inhibin levels around human labor

The changes in bioinhibin (B-inhibin) and immunoinhibin (I-inhibin) levels were studied in the serum of healthy term pregnant women by ovine pituitary cell culture and immunoenzymatic assay systems before and 24 h after delivery. In the maternal serum, a sharp decline in both B-inhibin and I-inhibin levels was observed within first 6 h after delivery. B-inhibin and I-inhibin in maternal serum were 3.45 +/- 0.25 and 3.77 +/- 0.43 U/mL, respectively, before labor and decreased by 35.82% and 38.89% 30 min after labor. One hour after delivery, B-inhibin and I-inhibin were reduced by 56.74% and 61.48%, respectively. After 6 h, B-inhibin and I-inhibin levels were lowered by 93.86% and 78.90%, respectively. Twenty-four hours later, both inhibins were nearly undetectable. In the retroplacental serum, B-inhibin and I-inhibin were 4.92 +/- 0.34 and 10.13 +/- 1.16 U/mL, respectively, i.e. 42.48% and 168.60% higher than the levels of B-inhibin (P less than 0.05) and I-inhibin (P less than 0.001) in maternal serum before delivery. In the umbilical cord serum, the B-inhibin concentration was 0.75 +/- 0.16 U/mL, whereas the I-inhibin concentration was 9.58 +/- 0.75 U/mL, which was much higher than that of B-inhibin (P less than 0.001). No difference was found in B-inhibin or I-inhibin levels in the serum samples collected separately from umbilical arteries and veins (P greater than 0.05). In addition, inhibin levels were measured in amniotic fluid and placental extract. In amniotic fluid, B-inhibin and I-inhibin concentrations were 2.37 +/- 0.35 and 8.01 +/- 0.55 U/mL, respectively. In the comparison, B-inhibin in amniotic fluid was 31.3% lower than that in maternal serum before delivery (P less than 0.05), but I-inhibin was 112.5% higher than that in the maternal serum (P less than 0.001). In the placental extract, the B-inhibin concentration was 12.80 +/- 0.35 U/g tissue, while the I-inhibin concentration was 33.86 +/- 2.93 U/g tissue, which was more than twice as high as the B-inhibin level (P less than 0.001). Our data provide further evidence that inhibin may be mainly produced in the placenta during pregnancy.

Inhibin production and secretion in human placental cells cultured in vitro

In this study, human trophoblast cells were isolated from term placentas by trypsin-DNase digestion and Percoll gradient centrifugation. After the cells were cultured in vitro, bioactive inhibin and immunoreactive inhibin were measured in the culture medium and cellular lysate by an ovine pituitary cell culture system and an immunoenzymatic assay. The trophoblast cells were capable of producing inhibin, as indicated by the observation that enhancement of inhibin content and secretion was dependent upon the cell number and time in culture. High levels of inhibin were observed in the culture medium and the cellular lysate with cell numbers of over 1 x 10(6) cells/well, whereas the inhibin levels decreased until they were nearly undetectable when the cell number was less than 0.25 x 10(6) cells/well. In the culture medium, a sharp increase of inhibin levels was observed after 2 days of culture. Bio-inhibin and immuno-inhibin concentrations in the culture medium increased tenfold and fourfold, respectively, from day 2 to day 4. The peak level of bio-inhibin (3.5 U/mL) occurred on day 4 and that of immuno-inhibin (3.55 U/mL) on day 6. In contrast, the maximal level of bio-inhibin (4.45 U/mL) and immuno-inhibin (4.25 U/mL) in the cellular lysate was observed on day 2.(ABSTRACT TRUNCATED AT 250 WORDS)

A study on the diagnosis of drowning by examination of lung chlorophyll(a) of planktons with a spectrofluorophotometer

An investigation on the diagnosis of drowning by analysis of chlorophyll(a) (Chl.(a)) of planktons in the lung sample with a spectrofluorophotometer (SFPM) is reported. The diagnostic criteria or main points of death by drowning are suggested are according to our experimental studies. Meanwhile two cases of submersion in water were investigated and the causes of death were diagnosed correctly. It is concluded that examination of lung Chl.(a) of planktons could be used as a reliable diagnostic method in forensic practice.

[Relationship between development of periodontitis and macrophage's defensive power against infection in rats fed a high-sucrose diet]

As mononuclear phagocytes have been implicated as important cellular elements in the process of bone resorption, we decided to study the relevancy of macrophage (M phi) activities to bone resorption. In this study, we investigated the phagocytic activity and activities of lysosomal enzymes of peritoneal resident M phi from rats fed a high-sucrose diet (Diet 2000) to appreciate the effects of Diet 2000 on systemic and local factors. Minkin et al. have postulated that bone-derived chemotactic factors were released from foci undergoing resorption. And so, we examined the effects of the supernatant from alveolar bone cultures (Bone-sup) prepared from rats fed Diet 2000 on the activities of glycogen induced peritoneal M phi. As a result we observed mild alveolar bone resorption with slight inflammation when the rats were fed Diet 2000 for six months. In the periodontal tissue, we found inflammatory cell infiltration, destruction of the periodontal ligament, and lacunae in the alveolar bone due to resorption. The phagocytic activity of M phi treated with Bone-sups was suppressed before the periodontal tissue, which is inflammatory condition such as alveolar bone resorption. Furthermore the phagocytic activity of resident M phi taken from rats on the Diet 2000 was suppressed. After one month of the Diet 2000, the activity of acid phosphatase (AcP), a lysosomal enzyme of M phi, was suppressed, but by six months it was enhanced. The activity of beta-N-acetyl-D-glucosaminidase (NAG), another lysosomal enzyme of M phi, was suppressed over the total period of Diet 2000 before the periodontal tissue was destroyed. These findings suggest that the capacity for defense against infection by M phi is suppressed when periodontitis is initiated by Diet 2000 feeding and that M phi activities are influenced by some factors elaborated by cells in the alveolar bone.

Reciprocal relations for transmission coefficients: theory and application

The authors present a rigorous proof of certain intuitively plausible reciprocal relations for time harmonic plane-wave transmission and reflection at the interface between a fluid and an anisotropic elastic solid. Precise forms of the reciprocity relations for the transmission coefficients and for the transmitted energy fluxes are derived, based on the reciprocity theorem of elastodynamics. It is shown that the reciprocity relations can be used in conjunction with measured values of peak amplitudes for transmission through a slab of the solid (water-solid-water) to obtain the water-solid coefficients. Experiments were performed for a slab of a unidirectional fiber-reinforced composite. Good agreement of the experimentally measured transmission coefficients with theoretical values was obtained.

Synchronization of amniotic fluid cells for high resolution cytogenetics

A high resolution technique was applied to amniotic fluid cells by synchronization. After inoculation, the cells were incubated for 30 h in the presence of either thymidine or 5-bromodeoxyuridine (BrdU). After removal of the blocking agent and addition of a low concentration of thymidine, the cells were incubated for another 6 1/2 7 h, then harvested in prometaphase without colcemid. This technique gives a mitotic index of 3.7 per cent after thymidine synchronization and of 3.2 per cent after BrdU synchronization, and more than half of the mitoses were in the earlier phases with the chromosomes showing more than 550 bands per haploid set. GBG, GTG, and RHG prometaphases are presented. Precise high-resolution banding of chromosomes of amniotic fluid cells can increase diagnostic accuracy.